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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /net/llc/llc_if.c
Initial import
Diffstat (limited to 'net/llc/llc_if.c')
-rw-r--r--net/llc/llc_if.c154
1 files changed, 154 insertions, 0 deletions
diff --git a/net/llc/llc_if.c b/net/llc/llc_if.c
new file mode 100644
index 000000000..6daf391b3
--- /dev/null
+++ b/net/llc/llc_if.c
@@ -0,0 +1,154 @@
+/*
+ * llc_if.c - Defines LLC interface to upper layer
+ *
+ * Copyright (c) 1997 by Procom Technology, Inc.
+ * 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
+ *
+ * This program can be redistributed or modified under the terms of the
+ * GNU General Public License as published by the Free Software Foundation.
+ * This program is distributed without any warranty or implied warranty
+ * of merchantability or fitness for a particular purpose.
+ *
+ * See the GNU General Public License for more details.
+ */
+#include <linux/gfp.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/errno.h>
+#include <net/llc_if.h>
+#include <net/llc_sap.h>
+#include <net/llc_s_ev.h>
+#include <net/llc_conn.h>
+#include <net/sock.h>
+#include <net/llc_c_ev.h>
+#include <net/llc_c_ac.h>
+#include <net/llc_c_st.h>
+#include <net/tcp_states.h>
+
+/**
+ * llc_build_and_send_pkt - Connection data sending for upper layers.
+ * @sk: connection
+ * @skb: packet to send
+ *
+ * This function is called when upper layer wants to send data using
+ * connection oriented communication mode. During sending data, connection
+ * will be locked and received frames and expired timers will be queued.
+ * Returns 0 for success, -ECONNABORTED when the connection already
+ * closed and -EBUSY when sending data is not permitted in this state or
+ * LLC has send an I pdu with p bit set to 1 and is waiting for it's
+ * response.
+ */
+int llc_build_and_send_pkt(struct sock *sk, struct sk_buff *skb)
+{
+ struct llc_conn_state_ev *ev;
+ int rc = -ECONNABORTED;
+ struct llc_sock *llc = llc_sk(sk);
+
+ if (unlikely(llc->state == LLC_CONN_STATE_ADM))
+ goto out;
+ rc = -EBUSY;
+ if (unlikely(llc_data_accept_state(llc->state) || /* data_conn_refuse */
+ llc->p_flag)) {
+ llc->failed_data_req = 1;
+ goto out;
+ }
+ ev = llc_conn_ev(skb);
+ ev->type = LLC_CONN_EV_TYPE_PRIM;
+ ev->prim = LLC_DATA_PRIM;
+ ev->prim_type = LLC_PRIM_TYPE_REQ;
+ skb->dev = llc->dev;
+ rc = llc_conn_state_process(sk, skb);
+out:
+ return rc;
+}
+
+/**
+ * llc_establish_connection - Called by upper layer to establish a conn
+ * @sk: connection
+ * @lmac: local mac address
+ * @dmac: destination mac address
+ * @dsap: destination sap
+ *
+ * Upper layer calls this to establish an LLC connection with a remote
+ * machine. This function packages a proper event and sends it connection
+ * component state machine. Success or failure of connection
+ * establishment will inform to upper layer via calling it's confirm
+ * function and passing proper information.
+ */
+int llc_establish_connection(struct sock *sk, u8 *lmac, u8 *dmac, u8 dsap)
+{
+ int rc = -EISCONN;
+ struct llc_addr laddr, daddr;
+ struct sk_buff *skb;
+ struct llc_sock *llc = llc_sk(sk);
+ struct sock *existing;
+
+ laddr.lsap = llc->sap->laddr.lsap;
+ daddr.lsap = dsap;
+ memcpy(daddr.mac, dmac, sizeof(daddr.mac));
+ memcpy(laddr.mac, lmac, sizeof(laddr.mac));
+ existing = llc_lookup_established(llc->sap, &daddr, &laddr);
+ if (existing) {
+ if (existing->sk_state == TCP_ESTABLISHED) {
+ sk = existing;
+ goto out_put;
+ } else
+ sock_put(existing);
+ }
+ sock_hold(sk);
+ rc = -ENOMEM;
+ skb = alloc_skb(0, GFP_ATOMIC);
+ if (skb) {
+ struct llc_conn_state_ev *ev = llc_conn_ev(skb);
+
+ ev->type = LLC_CONN_EV_TYPE_PRIM;
+ ev->prim = LLC_CONN_PRIM;
+ ev->prim_type = LLC_PRIM_TYPE_REQ;
+ skb_set_owner_w(skb, sk);
+ rc = llc_conn_state_process(sk, skb);
+ }
+out_put:
+ sock_put(sk);
+ return rc;
+}
+
+/**
+ * llc_send_disc - Called by upper layer to close a connection
+ * @sk: connection to be closed
+ *
+ * Upper layer calls this when it wants to close an established LLC
+ * connection with a remote machine. This function packages a proper event
+ * and sends it to connection component state machine. Returns 0 for
+ * success, 1 otherwise.
+ */
+int llc_send_disc(struct sock *sk)
+{
+ u16 rc = 1;
+ struct llc_conn_state_ev *ev;
+ struct sk_buff *skb;
+
+ sock_hold(sk);
+ if (sk->sk_type != SOCK_STREAM || sk->sk_state != TCP_ESTABLISHED ||
+ llc_sk(sk)->state == LLC_CONN_STATE_ADM ||
+ llc_sk(sk)->state == LLC_CONN_OUT_OF_SVC)
+ goto out;
+ /*
+ * Postpone unassigning the connection from its SAP and returning the
+ * connection until all ACTIONs have been completely executed
+ */
+ skb = alloc_skb(0, GFP_ATOMIC);
+ if (!skb)
+ goto out;
+ skb_set_owner_w(skb, sk);
+ sk->sk_state = TCP_CLOSING;
+ ev = llc_conn_ev(skb);
+ ev->type = LLC_CONN_EV_TYPE_PRIM;
+ ev->prim = LLC_DISC_PRIM;
+ ev->prim_type = LLC_PRIM_TYPE_REQ;
+ rc = llc_conn_state_process(sk, skb);
+out:
+ sock_put(sk);
+ return rc;
+}
+